GM plans a "100 MPG" (2,35 l/100 km) car within 2-3 years

probe

Can Automakers Build a 100-MPG Car?

By Chuck Squatriglia April 04, 2008 | 12:48:32


What would a 100-mpg car look like? According to General Motors, it will look a lot like the company's forthcoming Chevrolet Volt or Saturn Vue plug-in hybrid.

Despite the company's massive investment in hydrogen fuel cell technology -- which it remains absolutely committed to -- GM doesn't see the gasoline internal combustion engine going anywhere anytime soon. And while that workhorse of the industry is getting more efficient, GM's Bob Kruse said the only way it'll achieve triple-digit fuel economy is to mate it to an electric motor.
"We will be using internal combustion engines for awhile," Kruse, executive director of global engineering of hybrids, electric vehicles and batteries, said during an online chat this morning. "The 100-mpg car can be thought of as the Volt, (and) it will achieve this operating on a combination of electric and ICE propulsion."

The article continues at....http://blog.wired.com/cars/2008/04/can-automakers.html

http://www.youtube.com/watch?v=Mio5fTKqWgM

http://en.wikipedia.org/wiki/Peel_P50

100mpg car ^^^
Not a hybrid either
Built DECADES AGO



We should be way further ahead than we are today

bonkey

The Peugeot 308 HDi has achieved some rather impressive figures recently.

Officially rated at 4.7l/100km, it completed a round-trip of Australia averaging 3.13l/100km, which translates to just over 91 mpg.

It should be noted, of course, that this would have been set obeying the 100 km/h speed limit in Australia, and would have been almost-exclusively congestion-free driving.

Nonetheless, its an impressive result. How much further efficiency can be taken without going hybrid or abandoning the ICE completely is, of course, an open question.

If and when Peugeot manage to bring a diesel hybrid to market, if they can marry the same ICE efficiency with the benefits of hybrid tech, 100mpg will (hopefully) be left in the dust.

probe

bonkey wrote: »

The Peugeot 308 HDi has achieved some rather impressive figures recently.

Officially rated at 4.7l/100km, it completed a round-trip of Australia averaging 3.13l/100km, which translates to just over 91 mpg.

3.13 l/100 km = 75 MPG (US) to compare on a like for like basis in terms of GM's aspirations cited in the Wired.com article.

.probe

derry

Given unlimited budget and expensive solutions 100mpg could happen sooner but
to understand the problem its to do with where the biggest losses are

First car engine with the petrol fuel is ~30% efficient so ~60% fuel is wasted for starters or gets thrown out the exhaust stack as heat noise vibration mechanical losses whatever

In steady state driving at 55mph on the highway

There is drag from air drag
and from brakes always wearing against the disks
coupled with mechanical losses through gear box
rolling friction from tyres
and other factors
and the half of the engines ~30% efficiency is lost

so now the car is 15% efficient maxuim
( in what we called global efficiency where we look at all the factors)

~15% is best case on a good day with a following wind and is more often likely to be ~12% efficient

Throw in traffic accelerating stopping etc and ~6% efficiency is easy in most city driving so meaning a car that does half in highway and half in city would come in at ~10% efficiency best case expect les

so 90% the fuel is wasted somewhere and we arrive at a 10% global efficiency

cars that only drive in the city traffic will be worse and cars that only drive on free flowing highways will be better than that

So if a car is doing 33 MPG and you want 99MPG or three times better you need to figure where the losses are and try reduce them if possible


there are many factors but we will look a few

first is weight reduce weight of car by a third will reduce demand for the fuel to accelerate often i/3 weight drop will reduce fuel demands buy 10% sometimes more

second is air creates drag so if you reduce the drag from either driving more slowly or better shapes this will reduce fuel consumption

Third get engine to burn fuel or fuels better and lose less energy from bad burn in engine .Sometimes computer control engines can burn fuel better and that control method is geetiing cheaper and more possible to do right now without spending big money

The computer control can also allow the burning of different fuels like methanol ethanol and petrol and we say the engine is classed as flex fuel

One of the biggest energy losses is the engine itself it loses 60% in the form of heat noise and air friction


The air friction is one of the biggest power losses as it requires energy to suck air into engine and this accounts for ~50% of the lost 60% of the energy

If the fuel you use needs less air to burn you can suck in less air and save enegy
Petrol fuels require the most air to burn
various ideas as possible solutions are carry the air in air bottles and inject directly .
Alternatively there is the solution to carry a fuel that has more oxygen in it molecules or have a engine that has a better shape that creates less friction to suck in air such as more valves more injectors etc but that increases cost of engine

Fuels with high oxygen is alcohols such as methanol's and ethanol

Also with heat ejected reuse the energy to do something else and scavenge back some of the lost heat

Or catch the exhaust fumes compress them into bottles and re-use later but it requires energy to compress gas and the gas released back to engine would only work at slow speeds and compressing gas would require engine to be running at fairly high speeds

Noise from explosion in engines could be reduced with other fuels that explode less aggressively and lose less energy

The Alcohol fuels or alcohols fuels mixxes of petrol and alcohol can achieve this


If you can get engine from 30% efficiency to 60% efficiency your half way there but instead of typical 1600 cc engine which costs 3000 euros or similar expect costs to be

300,000 euros to achieve 60% efficiency
or 100,000 eurosto achieve 45% efficiency
or 10,000 eurosto achieve 40% efficiency
or 4000 eurosto achieve 38% efficiency

So realistically 38% is more a runner in todays world and in a few years time 40% will only cost 4000 in that time as cost drop with time

eg incremental advances are the norm in cars

Changing fuels to E85 or alcohol family like ethanol or methanol as these fuels have more oxygen on the molecule and therefore have a better burn ability
However there is a problem in that they burn more fuel as less of the fuel has carbon molecules the stuff that burns so you need the same amount of carbon to get heat and so therefore you need more fuel injected to ensure the amount of carbon molecules is eneogh

With pure petrol the air supply's all the oxygen but you lose power dragging in so much air to burn with the carbon part of the fuel

However the alcohol fuel burn is much smoother and with a lot less vibration or knocking
This smother running can go a long way to saving fuel requirements as less fuel wasted means less fuel needed

Carrying air bottles or liquid oxygen is too heavy and not a runner for continuous driving

For occasional intermittent large demands such as overtaking small short duration bottles can be useful and nitro oxide (laughing gas ) is used for street racing cars
But nitros oxide is complex and expensive

Other options are possible like changing to other more oxygen rich fuels like nitro methaane
This fuel will produce more power so a lighter engine is possible but it takes more energy to make the fuel from natural gas
This means in effect the engine is gaining energy from outside the fuel burn loop so net benefit is non when you do the global energy equation's

However local global benefits can increase as less air needed to be injected into engine but even more oxygen on the fuel molecule means a lot whole more fuel is needed

Nitromethane cost bulk cost $15 a gallon USA or $100 in small amounts

Assuming 25 euro a UK gallon or 5 time the price of petrool per gallon and it requires 4.5 times as much of that nitro methane fuel neat to produce the same millage as petrol and to supply similar power as petrol equivalent

A typical car that get 30MPG on petrol would only get 5 MPG using nitromethane and cost 50 times more for each mile but there are sometimes hidden benefits when mixed in lower ratios with other fuels

Using Pure nitro methane the engine ~600cc would be as powerful as the ~1600cc version
so a large affect to engine size is possible but the air requirement would be very reduced so plus ~30% friction drop in sucking in fuel could result

we can see we can gain in some sectors but lose in others

{sub note
Envioremental issues with complex nitrogen molecules

Also for the planet getting it goose cooked from CO2 global warming if you want to believe that stuff which is in there with the global ice age guys who tried to do our heads in with the imminent arrival of the icebergs in the 1970s will have issues with Nitrogen solutions as nitro solutions create nitrogen complex molecules exhaust gassers which are 300 times a more powerful global warming agents than co2 gasses but thats another days work whether co2 in parts per million( means hard to measure you try finding one red ball in a miilion white balls ) can create heat as more than 50% of the heat from the planet that is trapped is from water vapor at the first 30 feet of the surface of the planet so maybe we should ban water vapor or we can assume I am not of the CO2 religion follower having been previously deceived by the same snake oil ice bergs experts who predicted we were going to be squashed and I should sell up and run for africa
the same experts who changed camps to CO2 and cooked goose brigade }


Adding some 5% nitromethane family fuels to petrol cars would probably result in 15% gain in power and allow a 25% drop in engine weight and give the most for the least in terms of diminishing returns but increase fuel costs by 25% for a 5% input

if nitromethane was mass produced more the costs of that fuel could drop a lot to 5 euros a UK gallon but you will still lots more of it compared to Petrol

Burning more than 10% nitromethane can cause to many problems for nitro type pollution in the car exhaust system and swamp the catalistic converters that scrubs up nitrogen molecules in exhaust gas

Other tricks are ensuring correct size for the cylinder for the fuel
200cc to 350cc is the optimum size for a petrol fuel burning engine
that explains why most cars are
3 cylinder 300cc making 900cc engine
or 4 cylinders 250cc making a thousand
or 4 cylinders 350cc making 1350cc
or 6 cylinders of 350cc making ~2000cc ....and so forth

For other fuels it can be different like ethanol will cope with smaller cylinders but alcohol fuels prefer higher compression and so as a benefit will give more power than petrol fuels if the engine is made with higher compression but that higher compression will make motor heavier to cope with higher pressures and will cost more

flex fuel motors in this can change compression to cope with different fuels using computer control solutions

so there is the issue of swings and roundabouts

Scavenging the heat ejected from engine will probably require some form of steam engine solution to re -harness the heat and turn it into suitable power
This will incur extra weight to catch the heat and extra weight to supply the steam engine power source
Also it will require a suitable gearbox to connect steam power to normal car engine so that they work together

This will mean a fair chunk of extra weight but if it possible to capture say 30% of the lost heat so from the 60% ejected heat we might get back 20% of it

however we might just as easily lose most of that benefit from the extra weight to drag around the steam engine scavenger solution so again swings and roundabouts

Also the cost of the steam scavenger is probably easily going to be 3 times the cost of the main engine so three times 3000 euros suggest it would be 9000 euro making the engine components cost 12,000 euro

Now for the hapless car owner burning say 3000 euros of petrol a year he will probably require 20 years running of this steam engine internal combustion solution just to get back to breaking even
After paying this extra premium cost 9000 euros most owners sell the cars after a few years so they would be paying for something that they would not really benefit from

So unless fuel goes from a liter 1.20 euro its present price to 10 euro a liter the extra cost would be too high and would be unlikely to succeed

All predictions suggest is most unlikely for fuel to exceed 3 euros a liter in the next few years

So Its unlikely that heat scavenger solution will happen any time soon

The other sources of friction are WIND RESISTANCE

examples of a MPG of a typical family car 1600cc ford type salon
steady state driving highway
tank size 30 gallons
30 MPH 30 MPG range ~900 miles
50 MPH 22 MPG range ~660 miles
70 MPH 10 MPG range ~ 300 miles
100 MPH 4 MPG range ~ 120 miles

In cars a doubling of the speed from 30mph to 60 mph will quadruple the force against the car .To supply the power to double the speed you need to supply at least quadruple the power but often in reality we say 9 times so in simple terms
20BHP car at 30mph using say 100 grams of fuel a minute will require to do
60mph at least 80BHP but probably ~120BHp and will consume at least 400 grams of fuel per minute but probably more like 600 grams of fuel

so we can see that speed hurts fuel figures bad and when fuel crisis arrives the government simple solution to make fuel stretch further is a 55MPH speed limit

Accelerating and de-accelerating if we could arrange it better we could trap the energy in a giant flywheel when we break and release energy to accelerate and super light weight super high speed carbon fiber wheels on low friction bearing have been used in cars and buses with most benefit to buses who stop and start more frequently
However costs are still very severe expect 30,000 euros for the car version of the flywheel and that not including the cost of buying the rest of the car

For cars that always would run at steady state speeds on the highway they would get no benefit to carry this extra weight

Air resistance and the shape of the car rest on several important facts

The first is the speeds less than 30MPH the shape has very little affect on fuel figures so brick shaped vans at 30MPH are nearly as good as sleeker shapes
rolling resistance from tyres flexing is the biggest drag at slower speeds but tyre resistance tends to stay fairly static no matter what the speed is

At higher speeds air resistance kicks in hard and a bad shaped brick shape will at 60MPH require 30% more power and fuel to be pushed than a sleeker shape

At 100Mph a brick shaped car could require as much as three times as much power to drive than a well air dynamic sleeker shape
However the sleeker shape has its problems and the car interior space like luggage and engine compartments get very small and cramped and it increases production costs

However sleeker shapes are usably more heavy and more complex to make than simplex brick shapes and if the average speed the car drives at is less than 50mPH its often not worth the extra cost to make the sleeker shapes


With rolling resistance the smaller and more narrow the tyres the less the friction but also the less the grip so super thin tyres with high pressure like bicycle tyres would be optimum for straight line speed and fuel saving
however the cornering would be very bad and so larger tyres would be needed for normal safe road driving

So very quickly we can see to get further MPG in a car the best is to get a very small car like a Smart two seater drive 30MPH and keep the speed steady as possible and with todays solutions 60 Miles per gallon on 55 mph highway driving are possible from that class of car

Having a flex fuel car which has several tanks of fuels and will pull different ratios of different quality fuels from the different tanks according to demands could improve that to 80Mpg
examples such as using higher ratio of gasoline at slower speeds where less power is needed and higher ratios of
ALCOHOLS FUELS AND NITRO METHANES FUEL WHEN MORE POWER IS NEEDED
At more severe peak demand power requirement extra powerful fuels like nitro methane or extra oxygen injection could help using nitrous oxide or similar solutions

It adds some extra cost and complexity but the engine could still run if only one type of fuel was available and would supply the best fuels for the required certain loads the engine encounters in different driving situations

Computer traffic management real time links with cell phone solutions which continually allow traffic update information could allow saving
It would be able to ensure cars are not accelerating quickly to only find lights turning against them so unnecessary accelerations and braking would be reduced
The result could reduce fuel demands
If traffic was grid locked the computer could switch of car engines until traffic cleared

Those solution could take a light weight two seater up to 90 to 100 mpg on a UK gallon or 70 tom90 MPG on USA gallon

After that more high tech solutions could be CO2 scavenging solutions where CO2 gas bottles are carried to run engines at low speed traffic and could refill as the engine runs at faster speeds from hot exhaust gasses and fumes and re inject the compressed CO2 gas in slow traffic and gain 5% from this but that would be pricey but less complex than electric or steam equivalents

Also cruise control computer controlled cars would supply more steady right foot throttle control than humans with less rigid legs and feet which should gain 5% for fuel saving


Plastic is typically half the weight of metal so replacing a small car entirely in plastic except for engine could half the weight of the car and have a substantial affect fuel reductions but dont crash it

More radical and very expensive solutions where engine is made using ceramic materials instead of METAL WOULD ALLOW FOR ENGINES WHICH REQUIRE NO WATER TO COOL OR OIL TO LUBRICATE AND COULD REDUCE SIZE OF ENGINE CONSIDERABLY but this is still in the experimental stage and those engines are not bolted together but are one piece so you can never pull them apart to fix them


So to start to get 100MPG USA gallon cars is probably possible in 2 seater cars without spending huge amounts of money maybe at double the price of todays cars
However to get four seater's to do the same might easily require spending 10 times the prices than todays prices
At the price off fuel now or even in a few years its probably not going to happen soon but incremental improvements of 5% per year are possible at a 5% price increase per annum making 100mpg USA a possibility in 10 years or even less at a reasonable price

If governments decide that will be to slow they can with extra funds speed it up but short of war cutting of fuel suppplies that would be an unlikly event in this time

Derry

Tomk1

derry wrote: »

Given unlimited budget and expensive solutions 100mpg could happen sooner but

Wow what an answer

but its been built before decades ago

McSandwich

derry wrote: »

Scavenging the heat ejected from engine will probably require some form of steam engine solution to re -harness the heat and turn it into suitable power

Derry

Some interesting research which will hopefully lead to efficient ways to recover waste heat:

http://www.spectrum.ieee.org/jan08/5879

http://www.sciencedaily.com/releases/2007/06/070603225026.htm

derry

McSandwich wrote: »

Some interesting research which will hopefully lead to efficient ways to recover waste heat:

http://www.spectrum.ieee.org/jan08/5879

http://www.sciencedaily.com/releases/2007/06/070603225026.htm

Some good links there but its a bit like the single tree in the forest issue

For example we take a 15% global efficiency car that does 50MPG and put a electronic pizo gizmo into the exhaust pipe and we extract 5% extra power
Now we get 52.5 MPG and we tend to call this type of development incremental

However there might exist theoretically the possibility to get four cars to go 50 miles each for the same gallon of fuel ( that translates to 200mpg ) but to do this we might not burn the fuel inside an engine in the car

If this possibility worked this would mean we had succeeded to do a quantum jump in technology solutions

So before we look at a cars we need to look at power stations
Power stations like large gas electric stations where they use gazzillions of $dollars to make them get all the best solutions that exist to extract all,l the heat from the fuel

A seven stage Natural gas steam generator electric power station in 1990 in Holland achieved local 87% global efficiency
For various reasons controlling exactly the amount of air and burning fuels and various high tech solutions and recycling the hot steam etc it is possible to get very high local efficiency levels of 65% plus
Now the problem is the peak load day time electric production will stay the same output for the station all the time day and night meaning the night time low load will reduce efficiency at night to cope with lower loads and when we factor in the whole day output the efficiency drops down to more like local ~50% global overall

If we could plug in extra machines that could store up the wasted night time power production and use it in the day time we would extract extra efficiency from the power station

The logical thing to do is to make cars with suitable battery or capacitor solutions that would charge up at night and do their work in the day time

This means a win win the more efficient electric power station could supply more MPG per gallon of fuel burned

Example the typical medium 1600cc car has a 100 BHP(Brake horse power ) engine to drive it around mostly using 40bhp to do speeds of 50mph roughly and less when going slowly and rarely uses 100 bhp except at 95mph on a highway or similar

Assuming that we decide the average mileage per day required is 100 miles and we can live with a slower speed of 70mph we can build a car with a battery solution like NiMh (nickel methyl hydride )solutions that will supply 35BHP

With electric motors we can get as much as 90% efficiency returns from the electric power we supply to that motor with 80% more likely

This means a 100BHP petrol engine efficiency equals 30BHP power returns
So a 35 bhp electric motor will equal a 100BHP petrol motor and weigh a lot less

The car will be the same size but because the motor is electric smaller and more efficient

However lots of losses still exist air resistance rolling resistance accelerating etc

There are transmission loses from the electric power station and heat losses putting power into batteries

Approximately with electric cars that carry four persons we can expect global efficiency in the order of 50% of the energy we put in in a medium sized car
That is 4 times the petrol car which in most best cases would be 12.5 % global efficiency

Even if we factor in the energy to make the batteries and the recycling costs to remake the batteries and cycle life's of batteries etc we find the energy total global efficiency remains roughly the same

So we can presently get 200MPG from cars if we can accept a reduced range and use other solutions for the occasional 300mile plus journey or organize a battery quick swop out solution filling stations as the NiMh (nickel methyl hydride )takes 30 minutes to recharge

Now other makes of batteries exist that recharge faster or ultra capacitors but they remain unproven compared to NiMh (nickel methyl hydride ) which already exists

Gas powered electric power stations exist giving out power all night to charge up batteries which would use power that is normally wasted in low load factors for the electric power utility

So we start to see the incremental solution of gradual improvement of primitive 12.5% global efficiency machine compared to doing the same incremental increase on a quantum jump 50% global efficiency electric car solution means we can see that there can be more than one way to measure MPG and skin a cat

The problem that exists today is the NiMh electric car solutions costs the owner of it a lot more to buy as the battery costs alone are exceeding $5000 in the USA and $15000 E10,000 in rip off Republic Ireland and thats before we include the car

Basically the electric battery NiMh will do ~1500 to 1700 cycles before its dead
1500 cycles at 100 miles per cycle means 150,000 miles leads to 150000/E10,000 = 0.06 cents per mile

We can safely assume that each time we plug in battery to be recharged it buttons and will add maximum 1 cent per mile making costs of the battery solution add up to 6 cents plus 1 cent = 7 cents per mile

The shops which presently sell the electric cars will say 1 cent per mile
They wont include the battery wear and tear cycle life of say 10c to 50cents per mile depending on factors
But most of electric car shops presently use a AGB (acid glass mat )sealed recombining lead acid battery with a ~400 cycle life and battery replacement costs in Ireland EEEKKK often make it double the cost of petrol when all costs are factored in


Assuming other factors roughly 10 cents per mile isn't to unlikely for electricity and battery wear costs

So where is the problem
example one guy buys a petrol car E20,000 and uses E10,000 of fuel over say 10 years E1000 per year mpg say 30mpg at E6 per gallon goes 50,000 miles or 5000 miles per year and is 20 cents per mile
total E30,000
This guy probably spends 20,000 to buy car keeps it for three years and spends E3000 while he had it in fuel and sells car for say E15,000 so total cost E3000 fuel and E6670 or 30% depreciation = E9670 or ~E9500 for three years

Another guy buys electric but pays 30,000 for the same car as he effectively buys 150000 miles of fuel in advance which adds E10,000 extra to his purchase costs
so 10 years E10,000/10 = 1000 cost per year goes 50,000 miles or 5000 miles per year cost makes E10.20c per mile

total E30,000

This guy probably spends 30,000 to buy car keeps it for three years and spends E0000 while he had it in normal fuel and some E300 in electric charging costs and sells car for say E22,500 so total cost E300 and 7500 depreciation = E7800

So petrol is lose ~E9500 and electric lose ~E8000 over three years

But real world stuff even the prices are the same 20cent per mile the E10,000

the running costs loses are similar about 10% difference

However extra costs and potential saving can easily be wiped out when we factor in the costs of finance often at 10% plus interest APR
Also we factor in reselling prices for cars after say 3 years when most people sell and buying ten years fuel in advance and adding often 1/3 extra value to purchases is just a step to far for most joe soaps to commit to such big loans

The government gets lots of money in tax from fuel
Everybody changes to electric and the taxes disappears
The petrol stations would lose fuel sales
The electric power stations would have to make extra power sources in car parks and special electric swop out or filling stations

Its not going to happen electric cars that so fast unless there is a determined drive to stop wasting fuel at the present rates we do as the government gets to much tax money lolly from it and the car owners are unable to handle 1/3 extra purchase costs

Figure used are a tad on the lower side as its hard to factor in the prices with the high costs in Ireland

To help sales in electric cars in the world markets and Ireland the most popular solution is to keep the car price down in the E12000 to E20000 region so the cars are often made 2 seater's as 4 seater's could easily hit 35 to E40,000 in Ireland and similar ratio's for price premium overheads would exist world wide
Also the cars use cheaper much heavier lower cycle life AGB batteries with 400 cycle life and 50 mile ranges

Derry

BendiBus

derry wrote: »

The problem that exists today is the NiMh electric car solutions costs the owner of it a lot more to buy as the battery costs alone are exceeding $5000 in the USA and $15000 E10,000 in rip off Republic Ireland and thats before we include the car

Which is why Shai Agassi of Project Better Place is planning on subsidising the battery in exchange for a long term service contract. As he calls it, "the cell phone model"

http://www.marcgunther.com/?p=357

Even so, there’s a problem—many people don’t want to pay an extra $10,000 up front for a battery, not knowing how long it will take for them to get their money back in the form of reduced fuel costs. So Agassi isn’t asking for that money up ront. Instead, he intends to sell his customers the cars for much less than they cost, provided that they agree to long-term service plans that will supply them with electricity, battery changes when needed, replacement batteries, etc. He estimates that he could afford to give people a free car if they agree to sign onto a service agreement for six years.

This is the cell phone model—where you get the phone for free or at low cost by signing a long term contract—brought to the auto business.

http://www.projectbetterplace.com/